The addition of environmentally clean electrical generation capacity has been targeted by the electrical utility industry as a goal for the 1990's and beyond.
Integrated gasification, combined cycle (IGCC) electric power plants have been identified as an one option for reaching this goal. Such plants or systems integrate clean coal gasification plants with combustion gas turbines and steam turbine/generators (combined cycle).
In one 100 megawatt electric power generating facility of this character, an entrained flow gasification unit is used to produce the clean coal gas needed by the gas turbine. This gasification process requires that large quantities of oxygen be delivered to the gasifier (.about.18.times.10.sup.6 ft.sup.3 /oxygen per day, .about.95% purity). This oxygen is produced by conventional liquefaction.
The oxygen-producing facility, with its air and oxygen compressors and heat exchangers, is complex and is sited over a considerable area. It requires a large capital investment; and it imposes a significant, parasitic electrical demand on the facility.
Electrochemical techniques for producing oxygen by extracting that compound from air have also been proposed. U.S. Pat. No. 4,908,113 issued 13 Mar. 1990 to Marianowski et al. and the prior art cited in that patent disclosure processes of that character which employ a molten electrolyte to effect the separation. Among other drawbacks of this process is that of safely employing molten electrolytes in the quantities needed for the large-scale generation of oxygen.